Small gauge instruments for micro surgery

ABSTRACT

A surgical system combines a cannula and an instrument in a manner that allows small gauge instruments to be used effectively, with little or no bending with respect to the manipulating proximal side of the instrument. Such design overcomes the shortcomings of prior art, and applies to various microsurgical procedures, including ophthalmology, allowing the use of smaller endo-photocoagulation probes, illumination probes, combination probes, vitrectors, scissors, manipulators, picks, diathermy, and others. By using smaller gauge, patient recovery is expected to be faster.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of, and claims priority to, co-pendingU.S. application Ser. No. 14/639,663, filed Mar. 5, 2015, which claimspriority to U.S. Provisional Patent Application Ser. No. 61/948,329,filed Mar. 5, 2014, entitled “Small Gauge Instruments for MicroSurgery,” the disclosures of which are incorporated by reference hereinas though set forth in their entireties.

TECHNICAL FIELD

The subject matter of the present invention relates, generally, toreducing the size of instruments that are used in micro surgery; thus,reducing the trauma and recovery time for the patient. In retinasurgery, this includes, but is not limited to, laser probes forendo-photocoagulation, illumination probes used in the vitreous,vitrectors, instruments (knives, scissors, manipulators, picks, and thelike), multi-function probes, diathermy, and the like. In otherapplications, electrodes for sensing and/or delivering energy areincluded.

BACKGROUND

In the field of endo-photocoagulation laser treatment at the retinaduring eye surgery, it is desirable to reduce the size of the entry sitein order to have less trauma and recovery time for the patient.

Most often, and as in other fields is medical surgery, a trocar systemis used, whereby a cannula is inserted at the entry site with theassistance of a puncturing device/instrument. Once the cannula is inplace, the puncturing device/instrument is withdrawn and the cannulaserves as an opening that allows one or more device to enter through thecannula and into the surgical site where it is needed.

As the industry has moved toward smaller diameters (typically, 27 gauge,25 gauge, and 23 gauge, as opposed to the larger, 20 gauge), suchcurrent systems prove to have engineering limitations, as the smallgauge instruments tend to flex at the entry point when the direction ofthe instrument (generally via a hand held instrument base) is changed inorder to target other areas in the general proximity.

As the outside diameter of the cannula is always larger than the outsidediameter of the device to be inserted therethrough, it is important tonote that a 25 gauge instrument will use close to 23.5 gauge cannula,and a 23 gauge instrument will use close to 21.5 gauge cannula.

In practice, with the 23 gauge system, the entry wound diameter isreduced by about 15%, and for the 25 gauge system, it is reduced byabout 33%, in comparison with the 20 gauge system.

With the 25 gauge system, the flexibility of the instruments reached anupper limit that not all surgeons are comfortable with, opting insteadfor the larger 23 gauge system.

As for the 27 gauge system, the flexibility is reduced by using areinforcing sleeve that stays close to the cannula entry, using thephysics of a cantilever, where rigidity is the strongest at the base (orlateral movement is the lowest) compared to the distal end, as in thecase of U.S. patent application Ser. No. 11/268,928.

Such size and technique provides very little control over changing thedirection of the instrument and is used only in very simple operationwhere the target area is very small.

Hence, a new approach is needed in order to use smaller gaugeinstruments, increasing the level of manipulation by the surgeon, withthe least amount of sacrifice in performance.

SUMMARY

In recognition of the above-described problems, a solution is hereinproposed. With the decrease in instrument sizes, stiffening of theinstruments becomes more challenging, with the current state of the art.It becomes more convenient that the instrument relies primarily on therigidity of the cannula itself, by anchoring the instrument to thecannula.

As the cannula is typically around 4 mm long, bending it is notpractically possible, even at smaller sizes.

The advantage of such new approach allows for smaller cannulas and,thus, smaller instruments to be inserted through such cannulas, whilemaintaining similar control that is comparable to larger sizeinstruments when restricted to the current state of the art.

As an illustration, a 34 gauge tube can fit a 100 micron laser fiber,and such a tube can go through a 30 gauge cannula; thus, reducing theentry wound diameter by about 66% when compared to 20 gauge cannulas,60% when compared to 23 gauge cannulas, and 50% when compared to 25gauge cannulas, and still with minimal compromise to the effectivenessand maneuvering offered by the 20 gauge system that is restricted to thecurrent state of the art.

In a first embodiment, the cannula is geometrically similar to what iscurrently used, while the instrument mates at the base of the cannula,at the external surface of the cannula entry point.

In such arrangement, the instrument diameter connecting to the cannulais chosen so that it has a diameter that resists flexing, allowing thecannula to change direction independently of the instrument flexibility.Such instrument size would be typically 20 gauge or larger. Once theinstrument is engaged at the base of the cannula, the functioning (andsmaller) part of the instrument passes through the cannula and into thesurgical spot.

In some cases, the functioning part of the instrument may enter throughthe cannula prior to mating the instrument and cannula.

However, having a short instrument length allows for smaller instrumentsize, as the flexing would diminish. In case of longer instruments, alarger instrument size may be needed.

As the instrument is manipulated laterally at its handle, the attachedlarge gauge part of the instrument connecting to the cannula moves intothe desired position, and if needed, the functioning part of theinstrument is allowed to move in and out of the surgical spot usingsecondary manipulation at the instrument.

In a second embodiment, the cannula is geometrically similar to what iscurrently used, with the difference being that the instrument mates atthe base of the cannula at the internal surface of the cannula entrypoint.

In a third embodiment, the cannula is geometrically similar to what iscurrently used, with the difference being that the instrument mates atthe base of the cannula at the internal and external surfaces of thecannula entry point.

These and other features and advantages of the various embodiments ofdevices and related systems, as set forth within the present disclosure,will become more apparent to those of ordinary skill in the art afterreading the following Detailed Description of Illustrative Embodimentsand the Claims in light of the accompanying drawing Figures.

BRIEF DESCRIPTION OF THE DRAWINGS

Accordingly, the within disclosure will be best understood throughconsideration of, and with reference to, the following drawing Figures,viewed in conjunction with the Detailed Description of IllustrativeEmbodiments referring thereto, in which like reference numbersthroughout the various Figures designate like structure, and in which:

FIG. 1A illustrates a representative of the traditional design, priorart in a straight position;

FIG. 1B illustrates a representative of the traditional design, priorart in a flexed position;

FIG. 1C illustrates a representative of the sleeve reinforced design,prior art in a straight position;

FIG. 1D illustrates a representative of the sleeve reinforced design,prior art in a flexed position;

FIG. 2A illustrates the first embodiment of the present invention in thestraight position;

FIG. 2B illustrates the first embodiment of the present invention in theflexed position;

FIG. 2C illustrates the second embodiment of the present invention inthe straight position;

FIG. 2D illustrates the second embodiment of the present invention inthe flexed position;

FIG. 2E illustrates the third embodiment of the present invention in thestraight position;

FIG. 2F illustrates the third embodiment of the present invention in theflexed position;

FIG. 3A illustrates deployment (when needed) of the functioning part ofthe instrument for the first embodiment of the present invention;

FIG. 3B illustrates the retraction (when needed) of the functioning partof the instrument for the first embodiment (past the cannula) of thepresent invention;

FIG. 3C illustrates an optional retraction (when needed) of thefunctioning part of the instrument for the first embodiment (within andincluding the edges of the cannula) of the present invention;

FIG. 3D illustrates another optional retraction (when needed) of thefunctioning part of the instrument for the first embodiment (notreaching the cannula) of the present invention;

FIG. 4A illustrates deployment (when needed) of the functioning part ofthe instrument for the second embodiment of the present invention;

FIG. 4B illustrates the retraction (when needed) of the functioning partof the instrument for the second embodiment (past the cannula) of thepresent invention;

FIG. 4C illustrates an optional retraction (when needed) of thefunctioning part of the instrument for the second embodiment (within andincluding the edges of the cannula) of the present invention;

FIG. 4D illustrates another optional retraction (when needed) of thefunctioning part of the instrument for the second embodiment (notreaching the cannula) of the present invention;

FIG. 5A illustrates deployment (when needed) of the functioning part ofthe instrument for the third embodiment of the present invention;

FIG. 5B illustrates the retraction (when needed) of the functioning partof the instrument for the third embodiment (past the cannula) of thepresent invention;

FIG. 5C illustrates an optional retraction (when needed) of thefunctioning part of the instrument for the third embodiment (within andincluding the edges of the cannula) of the present invention; and

FIG. 5D illustrates another optional retraction (when needed) of thefunctioning part of the instrument for the third embodiment (notreaching the cannula) of the present invention.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

In describing the several embodiments illustrated in the Figures,specific terminology is employed for the sake of clarity. The invention,however, is not intended to be limited to the specific terminology soselected, and it is to be understood that each specific element includesall technical equivalents that operate in a similar manner to accomplisha similar purpose. Additionally, in the Figures, like reference numeralsshall be used to designate corresponding parts throughout the severalFigures.

As illustrated in FIGS. 1A-1B, a representative, prior art shows thetypical functioning of an instrument through a cannula.

In order to target an adjacent area, the instrument is manipulated bychanging the angle. The smaller the instrument, the more flexing isobserved.

Depending on the instrument, a certain flexing cannot be exceededwithout compromising its function.

The smaller diameters clearly show an increasing challenge toeffectively use the instrument

As illustrated in FIGS. 1C-1D, representative illustrations of the priorart show the typical functioning of an instrument through a cannula,using a sleeve reinforcement to limit the flexing.

As in FIGS. 1A-1B, flexing is still occurring between the base of thecannula and the instrument.

In this design, flexing is reduced; thus, allowing the use of smallerinstruments.

Such a design has its limitation, as smaller instruments will bendsharply at the base of the cannula, risking catastrophic failure,including but not limited to instrument failure or breakage of a fiberoptic caused by excessive bending.

Turning now to a discussion of the inventive aspects of the presentdisclosure, and as illustrated in FIGS. 2A-2B, a large sleeve 12surrounds and mates with the base 22 of the cannula 20 on the outside.

Manipulating the handle 14 of the instrument 10 causes the short cannula20 to reshape the entry location, without any stress or bending on thefunctioning part 18 of the instrument 10.

As illustrated in FIGS. 2C-2D, a large sleeve 12 is inserted and mateswith the base 22 of the cannula 20 on the inside.

Manipulating the instrument 10 causes the short cannula 20 to reshapethe entry location, without any stress or bending on the functioningpart 18 of the instrument 10.

As illustrated in FIGS. 2E-2F, a large sleeve 12 surrounds the wall ofthe base 22 of the cannula 20 and mates with the base 22 of the cannula20 on the inside and outside.

Manipulating the instrument 10 causes the short cannula to reshape theentry location, without any stress or bending on the functioning part 18of the instrument 10.

As illustrated in FIGS. 3A-3D, the functioning part 18 of the instrument10 can be deployed using a mechanical mechanism 30 that advances it intothe desired surgical position. In the fully retracted position, the tipof the functioning part 18 of the instrument 10 may be beyond the distalend of the cannula 20, within the cannula 20, or prior to the proximalpart of the cannula 20. These illustrations pertain to a firstembodiment.

As illustrated in FIGS. 4A-4D, the functioning part 18 of the instrument10 can be deployed using a mechanical mechanism 30 that advances it intothe desired surgical position. In the fully retracted position, the tipof the functioning part 18 of the instrument 10 may be beyond the distalend of the cannula 20, within the cannula 20, or prior to the proximalpart of the cannula 20. These illustrations pertain to a secondembodiment.

As illustrated in FIGS. 5A-5D, the functioning part 18 of the instrument10 can be deployed using a mechanical mechanism 30 that advances it intothe desired surgical position. In the fully retracted position, the tipof the functioning part 18 of the instrument 10 may be beyond the distalend of the cannula 20, within the cannula 20, or prior to the proximalpart of the cannula 20. These illustrations pertain to the thirdembodiment.

Having, thus, described exemplary embodiments of the subject matter ofthe present disclosure, it is noted that the within disclosures areexemplary only and that various other alternatives, adaptations, andmodifications may be made within the scope and spirit of the presentinvention. Accordingly, the present subject matter is not limited to thespecific embodiments as illustrated herein, but is only limited by thefollowing claims.

What is claimed:
 1. A surgical instrument comprising: a handle; a sleeveattached to the handle and adapted to selectively anchor with a base ofa cannula after the cannula is inserted into and held at an entry siteof an eye during a micro-surgical procedure, wherein the sleeve issurrounded by an inner circumferential surface of the base of thecannula when anchored with the base of the cannula; and an elongatefunctioning member extending from the handle and associated with thesleeve, wherein the functioning member is adapted to be inserted throughthe cannula during the micro-surgical procedure.
 2. The surgicalinstrument of claim 1, further comprising the cannula configured withthe base, wherein the cannula is adapted to be inserted into and held atthe entry site of the eye during the micro-surgical procedure.
 3. Thesurgical instrument of claim 2, wherein the base of the cannula isconfigured with an inner diameter larger than an inner diameter of aremainder of the cannula.
 4. The surgical instrument of claim 3, whereinthe inner diameter of the base of the cannula is larger than an innerdiameter of the entry site of the eye.
 5. The surgical instrument ofclaim 1, wherein the functioning member is further adapted to beinserted through the cannula after the cannula is inserted into and heldat the entry site of the eye during the micro-surgical procedure.
 6. Thesurgical instrument of claim 1, wherein the functioning member isfurther adapted to be inserted through the cannula before the cannula isanchored with the base of the cannula.
 7. The surgical instrument ofclaim 1, wherein the sleeve and the cannula, when anchored, at leastpartially reduce bending of the functioning member during manipulationof the surgical instrument.
 8. The surgical instrument of claim 1,wherein the sleeve is further adapted to additionally anchor with thebase of the cannula via an outer circumferential surface of the base ofthe cannula such that a portion of the sleeve surrounds the outercircumferential surface of the base of the cannula when the sleeve isanchored with the base of the cannula.
 9. The surgical instrument ofclaim 1, wherein the functioning member is at least partially disposedwithin the sleeve.
 10. The surgical instrument of claim 1, furthercomprising: a mechanical mechanism extending at least partially externalto the handle and connected, within the handle, to the functioningmember, the mechanical mechanism adapted to advance or retract thefunctioning member through the cannula during the micro-surgicalprocedure.
 11. The surgical instrument of claim 1, wherein the numericalvalue of the gauge of the sleeve is 20 gauge or less.
 12. A method ofanchoring a surgical instrument to a cannula for use during amicro-surgical procedure, the method comprising: inserting the cannulainto an entry site of an eye during the micro-surgical procedure,wherein the cannula is held at the entry site of the eye during themicro-surgical procedure; responsive to inserting the cannula into theentry site of the eye during the micro-surgical procedure, anchoring asleeve attached to a handle of the surgical instrument to a base of thecannula, wherein the sleeve is surrounded by an inner circumferentialsurface of the base of the cannula when anchored with the base of thecannula; and inserting a functioning member, wherein the functioningmember extends from the handle and is associated with the sleeve,through the cannula to effectuate the micro-surgical procedure.
 13. Themethod of claim 12, wherein the base of the cannula is configured withan inner diameter larger than an inner diameter of a remainder of thecannula.
 14. The method of claim 12, wherein the sleeve is additionallyanchored to the base of the cannula via an outer circumferential surfaceof the base of the cannula such that a portion of the sleeve surroundsthe outer circumferential surface of the base of the cannula when thesleeve is anchored with the base of the cannula.
 15. The method of claim12, wherein the functioning member is inserted through the cannula priorto inserting the cannula into the entry site of the eye.
 16. The methodof claim 12, further comprising: manipulating a mechanical mechanismextending at least partially external to the handle and connected,within the handle, to the functioning member to advance or retract thefunctioning member through the cannula.
 17. A surgical instrumentcomprising: a handle; a sleeve attached to the handle and adapted toselectively anchor with a base of a cannula after the cannula isinserted into and held at an entry site of an eye during amicro-surgical procedure, wherein the sleeve is surrounded by an innercircumferential surface of the base of the cannula when anchored withthe base of the cannula; and an elongate functioning member associatedwith the sleeve, wherein the functioning member is adapted for selectivelongitudinal movement relative to the sleeve, and wherein thefunctioning member is further adapted to be selectively inserted throughthe cannula during the micro-surgical procedure.
 18. The surgicalinstrument of claim 17, further comprising the cannula configured withthe base, wherein the cannula is adapted to be inserted into and held atthe entry site of the eye during the micro-surgical procedure.
 19. Thesurgical instrument of claim 18, wherein the base of the cannula isconfigured with an inner diameter larger than an inner diameter of aremainder of the cannula.
 20. The surgical instrument of claim 19,wherein the functioning member is further adapted for selectivelongitudinal movement within the sleeve.